Gear type pump



P 1962 F. L. THOMPSON 3,054,356

GEAR TYPE PUMP Filed March 30, 1959 2 Sheets-Sheet 1 FIG. 2. 4

INVENTOR. F20 yo' L. 72 044, 50

Sept. 18, 1962 F. 1.. THOMPSON 3,054,356

GEAR TYPE} PUMP Filed March 30, 1959 v 2 Sheets-Sheet 2 A TrozA/gr Hora L. How/P50) M8 W34 United rates Free 3,054,356 GEAR TYIE PUMP Floyd L. Thompson, El Monte, tjaliil, assignor of thirtyg1; percent to Thomas P. Mahoney, Pacific Palisades,

Filed Mar. 30, 1959, Ser. No. 802,795 1 Claim. (1. 103-125) This invention relates to a gear pump and more particularly to a gear pump wherein extremely high pressures and vacuums can be achieved.

Among the various embodiments of the gear pump of my invention, disclosed in detail hereinbelow, is a gear pump incorporated in a housing, said housing defining a pumping chamber in which there is disposed a worm gear. The pumping chamber is provided with inlet and outlet ports and a circular gear is located in the housing in encompassing relationship with the worm gear, the teeth of the circular gear engaging the continuous thread on the worm gear and serving as the means whereby the inlet is separated from the outlet port communicating with the chamber. To increase the lineal contact of the circular gear with the worm gear, the axis of the worm gear is inclined with respect to the plane in which the teeth of the circular gear are located.

By the provision of the embodiment of the invention referred to immediately hereinabove, extreme economy of construction can be attained in a pump which is characterized by the achievement of high pressure delivery from inlet port to outlet port. Furthermore, in the embodiment of the invention under discussion, the worm gear is supported along its entire length in the pumping chamber and thus the loads which are normally encountered in gear type pumps are substantially eliminated in the embodiment under discussion.

Another advantage of the gear type pump incorporating the inclined worm gear is the fact that the inclination of the worm gear exposes a much greater surface of the worm gear to the associated circular gear and thus the efliciency of the pump is greatly increased since a much more effective sealing engagement of the circular gear with the worm gear is obtained.

Since the axes of the circular gear and worm gear are relatively inclined, the more effective sealing action mentioned hereinabove is attained, and it is also possible to utilize a metal circular gear and worm gear which will sustain fluid pressures of an order not attainable by gears fabricated from other materials. In other embodiments of the invention disclosed hereinbelow, the worm gear is juxtaposed to the periphery of a spur gear rather than being encompassed by a circular gear, the spur gear engaging the thread on the worm gear as the worm gear is rotated.

Other objects and advantages of the invention will be apparent from the following specification and the accompanying drawings which are for the purposeof illustration only and in which:

FIG. 1 is aperspetcive view of the housing of the embodiment of the invention;

FIG. 2 is a vertical, sectional view taken on the broken I line 22 of FIG. 1;

FIG. 3 is a transverse, sectional view taken on the broken line 33 of FIG. 2;

FIG. 4 is an enlarged, fragmentary, sectional view of the circular gear incorporated in the embodiment of the inventionshown in FIGS. 1-3;

FIG. 5 is an enlarged, fragmentary, perspective view showing, the cooperative relationship between the spur gear and worm gear in another embodiment ofthe gear pump of my invention;

FIG. 6 is a perspective view showing another embodiment of the gear pump of my invention;

FIG. 7 is a sectional view taken on the broken line 7-7 of FIG. 6;

FIG. 8 is a transverse, sectional view taken on the broken line 88 of FIG. 7;

FIG. 9 is a vertical, sectional View taken on the broken line 99 of FIG. 7; and

FIG. 10 is a transverse, sectional view of an alternative embodiment of the gear pump of my invention.

Referring to the drawings and particularly to FIGS. 1-4 thereof, I show a pump 10 constructed in accordance with the teachings of my invention and incorporated in a housing 12. The housing 12 is constituted by an upper part 14 and a lower part 16, said upper and lower parts being maintained in operative engagement with each other by means of bolts or similar fasteners 18.

An inclined pump chamber 20 is formed within the housing 12 and is constituted by coincident bores 22 and 24 within the upper and lower parts 14 and 16 of the housing 12. Disposed within the bores 22 and 24, constituting the pump chamber 20, is a rotor 26 constituted by a worm gear 28 and having the continuous thread 30 provided upon the periphery thereof in sealing engagement with the respective Walls of the bores 22 and 24. The lower extremity of the rotor 26 is provided with a journal 32 which is received in a bearing 34, while the upper extremity thereof has a shaft 36 provided thereupon journaled in a pillow block 38 which is secured 'by means of fasteners 40 to a contiguous portion of the housing 12. An O-ring 42 or similar sealing means is interposed between the contacting surfaces of the upper and lower parts :14 and 16 of the housing 12, to create a seal therebetween.

An annular recess 44 is formed in the upper surface 46 of the lower part 16 of the housing 12, said annular recess being disposed in a horizontal plane and encompassing the pump chamber 20 at the mating line between the bores 22 and 24 in the upper and lower parts 14 and 16 of the housing 12. As a matter of fact, the inner circumference of the annular recess is coincident with the outer circumference of the pump chamber 20, as at 50.

Mounted in the annular recess 44 is a circular gear 52, said circular gear being adapted to rotate in said recess and having a plurality of teeth 54 formed on its inner circumference and adapted to engage the continuous thread 30 on the periphery of the worm gear 28. The teeth 54 have angularly inclined contact faces 56 adapted to engage with and mate upon the correspondingly inclined portions of the thread 30 on the worm gear 28, in order to establish a fluid sealing relationship therewith and to accomplish the pumping of fluid disposed in the pump chamber 20. It will, therefore, be seen that the inclination of the axis of rotation of the worm gear 28 to the axis of rota tion of the circular gear 52 will, in addition to accomplishing the extended contact between said gears mentioned hereinabove, also permit the worm gear 28 to rotate the circular gear 52 to achieve the pumping action thereof. Thus, the timing and drive gears customarily utilized in gear pumps are eliminated.

To facilitate rotation of the circular gear 52 in the annu'lar recess 44, ball bearings 58 may be provided in the bottom wall of the annular recess 44 in engagement with the underside of the circular gear 52. If the pump 10 is to' be reversible bearings 58 may be installed in contact with both faces of the gear 52. If desired other types of bearing expedients than balls may be utilized.

Ports 60 and 62 communicate with the opposite extremities of the pump chamber 20 and, depending upon the direction of rotation of the rotor 26, are adapted to serve either as inlet or outlet ports. If desired the rotor 26 may 4 have a thrust bearing 64 formed thereupon or associated therewith to support the loadwhich arises when the thread 30 on the rotor engages the spur gear 52.

When the shaft 36 of the rotor 26 is secured to an appropriate source of power, such as an electric motor, not shown, rotation of the rotor 26 will take place. Concomitantly, the circular gear 52 will be rotated by the engagement of the teeth 54 thereof on the thread 30 of the rotor 26. Therefore, if the ports 60 and 62 are connected to a fluid source, the corresponding rotation of the rotor 26 and the circular gear 52 will cause fluid to be pumped from the port 62 through the pump chamber 20 and out the port '60, or vice versa, depending upon the direction of rotation of the rotor 26. Thus, the pump of my invention is completely reversible and the mere reversal of the direction of rotation of the rotor 26 will cause corresponding reversal of the flow of fluid therethrough. Because of the relative inclination of the axis of the rotor 26 to the horizontal plane in which the circular gear 52 is disposed, the teeth 54 engage the peripheral thread 30 upon the rotor 26 to a much greater extent than would -be the case if the axes of the rotor 26 and circular gear 52 were disposed at a right-angle to each other.

During the rotation of the rotor 26 and the circular gear 52 they are respectively supported in the pump chamber and the annular recess 44 throughout their entire circumferences, thus materially reducing the loads customarily encountered in conventional types of gear pumps and materially increasing the operative life thereof. In addition, a simple construction characteristic of the pump 10 will materially reduce the cost of fabricating the same. Another embodiment of the pump of my invention is shown schematicallyin FIG. 5 of the drawings wherein there is illustrated the combination of a rotor 70 disposed on a horizontal axis and having a continuous peripheral thread 72; A crown type gear 76 is mounted with its teeth 78 depending into and engaging the successive portions of the thread 72. As will be evident to those skilled in the art, the rotor 70 and crown gear 76 maybe mount ed in a housing, not shown, with the rotor 70 disposed in the pump chamber and the crown gear located in a horizontal recess in the housing which intersects a portion of the length of the pump chamber. As is evident from the previously discussed embodiment of the invention, the pump chamber is provided with inlet and outlet ports adapted to permit fluid to be respectively drawn into and expelled from the pump chamber by conjoint action of the rotor 70 and the crown gear 76.

Another pump 80 constructed in accordance with the teachings of my invention, is shown in FIGS. 6-9 of the drawings and includes a housing '82 having an upper part 84 and a lower part 86, maintained in operative relationship with each other by means of bolts or similar fastenrotation in the recess 114 is a spur gear 120 having teeth 122 adapted to engage the thread 102 of the rotor The spur gear incorporates a stub shaft 124 which is received within the counter-bore 116.

Therefore, as the rotor 100 is rotated in the desired direction, corresponding rotation of the spur gear 120 takes place causing fluid to be pumped from one extremity of the pumping chamber 90 to the other. .Reversing the direction of rotation of the rotor 100 will cause corresponding reversal of the fluid flow between the ports 96.

Shown in FIG. 10 of the drawings is an alternative embodiment of the invention wherein the parts corresponding to those of the previously described pump 80 are designated by corresponding reference numerals. The pump is generally similar in construction to the pump 80 but differs therefromin that the rotor 142 thereof is of hour-glass configuration and is disposed in a pump chamber 144 which corresponds generally to the configuration of the rotor 142 intermediate its extremities. The pump chamber 144 is formed in the upper and lower parts 146 of the housing 148 of the pump 140 and has ports in communication therewith.

By forming the rotor 142 with the hour-glass configuration, the teeth 122 of the spur gear 120 are adapted to engage the total length of the rotor, thus providing for a more effective fluid seal and greatly increasing the efficiency of the pump 140.

I thus provide by my invention a gear type pump which is characterized by the simplicity of its construction and the efficiency of its operation. The pump of myinvention may be utilized in high pressure applications and will serve as a positive fluid lock to prevent excessive leakage therethrough when the pumping action has ceased. The pump of my invention is completely reversible and is thus capable of being utilized in a wide variety of applications.

I claim as my invention:

In a pump, the combination of a housing having an elongated pump chamber and an inlet port communicating with one extremity thereof and an outlet port communicating with the other extremityrthereof, said housing incorporating an annular guideway and bearings adjacent the opposite extremities of said chamber; aflat, annular gear having involute teeth mounted for rotation in' said guideway in sealing relationship therewith; and an elongated worrn gear having an' external, axially extending helical thread in sealing relationship with said chamber, said worm gear being rotatableinsaid bearings and disposed within,. ccentric to and extending through said annular gear with its axis inclined, to the axis of said annular gear, saidworm gear beingpositioned so that said thread is fully meshed withs-aid annular gearteeth at ers 88, A horizontally disposed pump chamber 90 is formed in the housing 82 by means of cooperating semicircular recesses 92 and 94 in the upper and lower parts 84 and 86, respectively, of the housing 82. Ports 96 communicate with the opposite extremities of the chamber 90.

Disposed for rotation in the pump chamber 90 is a rotor 100, said rotor having a continuous spiral thread 102 thereupon which engages the contiguous wall of the pump chamber 90 and is adapted to propel fluid through the pump. chamber from one port 96 to the other, depending upon the direction'of rotation of the rotor 100. The rotor 100 incorporates a shaft 104 at one extremity which is journalled in a bearing 106 and a drive shaft 108 at its opposite extremity 'which'is journalled in a bearing 110. The drive shaft 108'protrudes through the bearing and is adapted to be engaged by a source of motive power such as an electric motor, not shown, to cause rotation of the rotor 100 in the desired direction within the pump chamber 90.

A circular recess 114 is formed within the upper'part 84 of the housing '82 andis "counter-bored at 11 6as shown in FIG. 9 of the drawings; A portion of the perimeter of the recess 144 intersects the pump chamber 90 at 118, as best shown in FIG. 8 of the drawings. Mounted for one point of the inner periphery of said annular gear and intermediate the extremities of said worm gear, said worm gear having a diameter substantially less than the internal diameter of said annular gear and having an axial length substantially greater than said annular gear,

' whereby, when said worm gear is rotated, said annular gear rotatestherewith so that fluid flowing into said cham- 1 17,516 Rarnsden June 9, 1857 612,304 Blazer n =Oct. 11, 1898 959,533 Holst May 3 1, 1910 1,164,276 Fogarty Dec. 14, 1915 1,323,459 D011; .Dec. 2, 1919 1,723,157 Guttinger Aug. 6, 1929 1,735,477 Stuart Nov.- 12, 1929 (Other references on following page) UNITED STATES PATENTS 2,402,805 COUSilIlO June 25, 1946 1 7 3 31 k Jul 1 1930 2,471,813 Cousillo y 1949 1 735 140 Morris 81 1930 2,716,861 Goodyear P 6, 1955 1 3 1 155 Douglas May 31 1932 2,908,226 Rich et a1 ()ct- 1959 1,946,097 MOITiS et a1 Feb. 6, 1934 5 1,989,552 GOOd Jan. 29, 1935 FOREIGN PATENTS 2,058,230 Hornbostel Oct. 20, 1936 366,604 Great Britain Feb. 11, 1932 2,158,933 Good May 16, 1939 

